//=============================================================================
//     _   _                               ____                _  _          
//    | | | |  __ _  _ __   _ __   _   _  / ___|  _ __   _ __ (_)| |_   ___ 
//    | |_| | / _` || '_ \ | '_ \ | | | | \___ \ | '_ \ | '__|| || __| / _ \
//    |  _  || (_| || |_) || |_) || |_| |  ___) || |_) || |   | || |_ |  __/
//    |_| |_| \__,_|| .__/ | .__/  \__, | |____/ | .__/ |_|   |_| \__| \___|
//                  |_|    |_|     |___/         |_|                         
//
//                     HappySprite - We make sprites happy
//
// Copyright (c) 2007 by Tank Monkey Games
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//=============================================================================

using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Xna.Framework;

namespace HappySprite.Simulation
{
    public class Circle : CollisionShape
    {
        float radius;

        public Circle(float radius)
        {
            this.radius = radius;
        }

        public Circle()
            : this(1f)
        {
        }

        public float Radius
        {
            get { return radius; }
            set { radius = value; }
        }

        public override ShapeType ShapeType
        {
            get { return ShapeType.Circle; }
        }

        public override BoundingRectangle GetBounds(Transform2D t)
        {
            float scale = Math.Max(t.Scale.X, t.Scale.Y);
            float scaledRadius = radius * scale;

            return new BoundingRectangle(
                t.Position.X - scaledRadius,
                t.Position.Y - scaledRadius,
                t.Position.X + scaledRadius,
                t.Position.Y + scaledRadius);
        }

        public override Vector2 SupportMapping(Vector2 v)
        {
            if (v.LengthSquared() < 1e-10f)
                return Vector2.Zero;

            Vector2 vnorm = Vector2.Normalize(v);
            return radius * vnorm;
        }
    }
}
